Keku Strait conditions

[DDW]

Thanks, will be looking forward to that report. We would be coming through soon after.

I'd assume that these are rocks and don't move much, so provided the charting is reasonably accurate the buoys are helpful but not really necessary. Not like a Florida inlet where they move them to suit the sand every couple of weeks.

What would be really interesting is a track through there. Usually chart plotters will keep a track and it is exportable (and thus importable elsewhere) from the plotter as a .gpx file. For the stretch, would probably need to be in fairly high resolution to be a useful example. I was able to import your route which seems completely logical.

 

[tpbrady]

DDW,

What file format do you need? Maybe Coastal Explorer can produce it.

Tom

 

[DDW]

I'm sure it can. The file will be a .gpx file (these are XML format, almost human readable with notepad etc.). I'd be importing it into the Raymarine Axiom and OpenCPN. Both will import a .gpx file. It is the same structure and format as a route, but generally has a lot more waypoints stored as data records with time, lat/long, and optionally some other metadata such as SOG.

These can also be imported and overlaid on Google Earth or other satellite maps.

 

[tpbrady]

Keku St GPX Files

Attached are the GPX files. I split the routes at Devils Elbow for planning purposes so there are 2 files.

Tom

 

[DDW]

Thanks Tom, but those appear to be routes, as opposed to tracks. The track would be the actual recorded GPS position of the boat as it went along, and the points will be a few seconds to a few minutes apart. Usually they are "adaptive" meaning points no more than X far apart, so fewer if you are moving slowly and more if moving fast. A track will be a much larger file than a route (though still not very big - perhaps 100KB for a track through the Rocky).

Some software will attempt to produce a route from a track when exporting (it does this by decimating the data to a reasonable number of waypoints). Maybe that is what happened? As an example of a track, here is our 2019 track from Prince Rupert to Wrangell. if this is imported as a route, it will have a huge number of waypoints.

View attachment 2019 Wrangell.gpx

 

[tpbrady]

DDW

Here is the same export but the actual track from the other day. It pretty much follows the route except for rounding off the turns.

Tom

 

[DDW]

Not attached?

 

[tpbrady]

I see why they didn't attach. They are exceed the file size limit for a GPX file. PM me your email address and I will send them that way.

Tom

 

[tpbrady]

Just passed through Rocky Pass with light to moderate kelp south of Devil's Elbow and at the south 1/4 of the Summit. Had a pod of orcas pass about 30ft from us between Devil's Elbow and the Summit. It happened so fast the only picture was bubbles.

Tom

 

[DDW]

Thanks for the update. We are still about 3 1/2 weeks away from attempting it. With so much rain forecast maybe the kelp will grow slowly.

 

[DDW]

We came south through the Keku and Rocky Pass a couple of days ago. It really isn't all that treacherous - though parts of it hold your attention - made much easier with modern navigational tools. I found the Navionics charts to be adequately accurate, as were the old NOAA raster charts - either one, combined with GPS positioning will get you through. I had the side scanning sonar on the whole time, least depth was about 6' (corrected to MLLW) in the Summit channel. As we were near the peak of a 10' tide we had 16'. The kelp was thickest south of the Devils Elbow, I did have to run through some but it was not terribly thick (but it has not been a particularly sunny Summer). The hype about the horrible 90 degree turn in the Elbow is a bit exaggerated, more of an easy arc, at least for a smaller trawler. Max current was 2.7 knots in the Summit channel, we arrived about 1 hour before the predicted high slack.

We found daymark 37 leaning badly and about to be lost, daymarks 39, 18, and 10 missing entirely, as well as the red can 10. These might be slightly missed if navigating with a chart and eyes, but are of little consequence in the GPS era.

Thanks to Tom for his knowledge and info.